Dysregulation of a gene that encodes an enzyme involved in lipid metabolism may contribute to hyperglycemia-induced insulin resistance in patients with type 2 diabetes, reports a team of scientists from Sweden, Finland, China, Japan, and the United States (Chibalin AV et al. Cell. 2008;132:375-386).
The researchers discovered that expression of a “fat-burning” enzyme, diacylglycerol kinase γ (DGKγ), is reduced in muscle tissue of patients with type 2 diabetes who have high blood glucose. Studies in diabetic rodents found the animals had reduced levels of DGKγ protein and DGKγ activity, which could be restored with successful treatment of the animals' blood glucose levels. The researchers also found that mice genetically engineered to express reduced levels of DGKγ in muscle and fat developed impaired insulin sensitivity and obesity.